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以琴叶风吹楠2年生苗木叶片为试验材料,比较叶面积法和称重法,95%乙醇、80%丙酮、丙酮-乙醇(2∶1)、试剂盒等4种提取液,和叶样研磨、不研磨处理对提取叶绿素含量的影响,试验结果:叶面积法得到的叶绿素a、叶绿素b和叶绿素总含量与SPAD值的相关系数远大于称重法;在直接浸提条件下,叶面积法4种提取液得到叶绿素总含量均值分别为3.9686、5.9621、6.0023、6.5956 mg/dm2,称重法得到叶绿素总含量分别为1.7353、2.4773、2.6695、2.7669 mg/g,提取效果排序为试剂盒丙酮-乙醇(2∶1)80%丙酮95%乙醇;混合提取液的提取效果均显著高于单一乙醇提取液,而混合提取液之间无显著差异;4种提取液提取研磨处理叶样的叶绿素总含量均值分别为6.088、6.513、6.429、7.278 mg/dm2,不研磨处理提取的叶绿素总含量分别为2.698、5.969、5.627、5.751 mg/dm2,研磨法提取效果较好。试验表明,用叶面积法,叶样研磨处理,以丙酮-乙醇(2∶1)为提取液的方法是较好的琴叶风吹楠叶绿素提取方法。 相似文献
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香菇多糖提取纯化研究 总被引:8,自引:0,他引:8
用0.2mol/L三氯乙酸、0.2mol/L氢氧化钠、1.0mol/L乙酸、蒸馏水为提取溶剂,结合超声波处理等方法从香菇子实体中提取香菇多糖,提取液经甲醇除杂、沉淀处理得粗多糖。粗多糖用CTAB络合沉淀,沉淀物乙酸溶解后取上清再用甲醇沉淀,沉淀物冻干得纯化多糖。分析检测结果显示干香菇三氯乙酸提取的纯化多糖的含量高达93.1%、提取得率达0.324%。薄层分析表明,纯化香菇多糖由葡萄糖、甘露糖、半乳糖、木糖组成。纯化多糖用Sephadex G-100凝胶层析,洗脱液经苯酚-硫酸法检测为单一吸收峰,红外光谱显示其具有多糖类的特征吸收峰。 相似文献
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混合液法测定叶绿素含量的研究 总被引:26,自引:0,他引:26
长期以来人们应用Arnon法测定叶绿素含量。此法是将材料在80%丙酮溶液中研磨并经过滤或离心除去残渣后,测定提取液的光密度值来计算叶绿素含量。1979年J.D.Hiscox等提出用二甲基亚砜(DMSO)直接浸提高等植物叶绿素,同样是测定提取液的光密度值来计算叶绿素含量。作者对以上两种 相似文献
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樟油的提取及其抑菌性研究 总被引:2,自引:0,他引:2
通过蒸馏法从樟树的树根、树枝、鲜叶及落叶中提取樟油,然后将用蒸馏法从落叶中获得的樟油和用丙酮浸提法从落叶中获得的提取物分别配制成不同浓度的水溶液,采用抑菌圈法分别对常见的几种细菌进行抑菌研究,结果表明落叶中的得油率最高,用蒸馏法获得的樟油对大肠杆菌(Escherichia coli)、普通变形杆菌(Proteus vulgaris)、金黄葡萄球菌(Staphylococcus aureus)有一定的抑菌作用,其最低抑菌浓度(MIC)在0.125~0.25 g.mL-1之间,而丙酮浸提液对上述细菌的生长几乎没有抑制作用。 相似文献
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金樱子黄酮类化合物提取条件研究 总被引:7,自引:0,他引:7
在60℃条件下,分别用水、不同浓度的丙酮和乙醇作溶剂来提取金樱子黄酮,通过比较提取液中金樱子黄酮含量,得出丙酮法是3种提取法中的最优方法。对丙酮法做正交实验,得到金樱子黄酮类化合物提取的优化条件。虽然乙醇法不及丙酮法效果好,但考虑到乙醇成本低、易操作,故对乙醇法也做了正交实验。结果表明,丙酮法提取金樱子黄酮类化合物的最佳条件:丙酮浓度为70%、水浴温度为50℃、固液比为1∶100、提取液中黄酮含量为0.7570mg/ml;而乙醇法最佳提取条件:乙醇浓度为60%、水浴温度为70℃、固液比为1∶150、提取液中黄酮含量为0.7030mg/ml。 相似文献
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通过室内饲养繁殖和野外采集,获得含有各龄桑天牛幼虫的杨树枝干,室内条件下分龄收集幼虫虫粪。对各龄幼虫虫粪进行区分,分离出粪粒和啃食残渣,对最末排粪孔长径和短径以及粪粒的理化性质与龄数关系进行研究。结果表明:桑天牛幼虫粪粒平均宽度值为1.211 5 mm,平均长度值为2.101 8 mm;粪粒中木屑平均宽度值为0.113 0 mm,平均长度值为0.207 3 mm;粪粒中蛋白质的平均含量为0.142 6%,总糖的平均含量为0.612 5%,纤维素平均含量为46.72%,木质素平均含量为16.12%。最末排粪孔长径和短径、粪粒长度和宽度、粪粒中木屑长度和宽度、纤维素含量、蛋白质含量均与幼虫龄数存在线性相关性,可作为快速识别幼虫龄数的指标,其中粪粒宽度比较稳定,在各龄数间无重叠,为林间快速识别虫龄的最佳指标。 相似文献
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Silicic acid: boric acid complexes as wood preservatives 总被引:1,自引:0,他引:1
Haruhiko Yamaguchi 《Wood Science and Technology》2003,37(3-4):287-297
Wood was treated with a low molecular-weight silicic acid: boric acid agent and examined for increased resistance to termites and combustion. Wood treated with silicic acid only exhibited increased termite resistance, but not to the marked extent observed after treatment with a mixture of silicic and boric acids. Increasing the quantity of boric acid also increased the termite mortality rate and shortened the time to death. Oral-toxicity tests using dyed silicic acid: boric acid suggested that the boric acid in the agent acted as a stomach poison. Field tests on stakes over three years showed that even if stakes were placed near the termite exit, those treated with silicic acid and high levels of boric acid had no attack by termites and maintained their original form. Though these specimens were installed in the field during three rainy seasons (about six months in total) in three years, the termite resistance ability of these chemicals was maintained. It became clear that this silicic acid: boric acid agent has a high water resistance ability worthy of application in the outdoors. Combustion tests showed that flame and glowing combustion times were shortened at high levels of boric acid. When a boric acid: methanol solution was added at of rate of not less than 25 ml for 100 g of colloidal silicic acid solution (CSAS), flaming and glowing combustion were not observed. Although the charring length of the wood specimen which was treated with a low molecular weight silicic acid: boric acid agent decreased to 2/3 of that of the control wood, the charring lengths were not influenced by the level of boric acid. However, the volume of smoke decreased relative to the amount of boric acid that had been added. 相似文献
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柳杉人工林皆伐后初期土壤有机碳和微生物量碳动态 总被引:3,自引:0,他引:3
本文研究了华西雨屏区柳杉人工林皆伐后1年内土壤有机碳和微生物量碳动态。结果表明:柳杉人工林皆伐林地土壤平均有机碳含量比对照(未皆伐林地)减小2.01 gC.kg-1,但差异不显著,而土壤平均有机碳储量及微生物量碳分别比对照减少20.97 tC.hm-2、6.68 mg.kg-1(P0.05);皆伐林地土壤有机碳含量及微生物量碳均随季节的变化而逐渐降低,但有机碳储量随季节的变化无明显减少趋势;皆伐林地土壤四季的有机碳含量、碳储量和微生物量碳差异不显著。皆伐对柳杉人工林土壤有机碳储量的影响主要表现在0~20 cm土层(P0.05);皆伐林地和对照在0~40 cm土层的微生物量碳和有机碳含量都表现出显著相关性(P0.05),但对照的相关性高于皆伐林地。总之,柳杉人工林转变为采伐迹地后,其初期土壤有机碳储量和微生物量碳都明显减少。 相似文献
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Zhiqiang Ma Xinyu Zhang Chuang Zhang Huimin Wang Fusheng Chen Xiaoli Fu Xiangmin Fang Xiaomin Sun Qiuliang Lei 《林业研究》2018,29(4):953-962
Nitrogen(N) and phosphorus(P) additions can affect soil microbial carbon(C) accumulation.However,the mechanisms that drive the changes in residual microbial C that occur after N and P additions have not been well-defined for Chinese fir plantations in subtropical China.We set up six different treatments, viz.a control(CK), two N treatments(N_1: 50 kg ha~(-1) a~(-1); N2:100 kg ha~(-1) a~(-1)), one P treatment(P: 50 kg ha~(-1) a~(-1)),and two combined N and P treatments(N_1P:50 kg ha~(-1) a~(-1) of N+50 kg ha~(-1) a~(-1) of P; N_2P:100 kg ha~(-1) a~(-1) of N+50 kg ha~(-1) a~(-1) of P).We then investigated the influences of N and P additions on residual microbial C.The results showed that soil pH and microbial biomass decreased after N additions, while microbial biomass increased after P additions.Soil organic carbon(SOC) and residual microbial C contents increased in the N and P treatments but not in the control.Residual microbial C accumulation varied according to treatment and declined in the order: N_2PN_1PN2N_1PCK.Residual microbial C contents were positively correlated with available N, P, and SOC contents, but were negatively correlated with soil p H.The ratio of residual fungal C to residual bacterial C increased under P additions, but declined under combined N+P additions.The ratio of residual microbial C to SOC increased from 11 to 14%under the N_1P and N_2P treatments, respectively.Our results suggest that the concentrations of residual microbial C and the stability of SOC would increase under combined applications of N and P fertilizers in subtropical Chinese fir plantation soils. 相似文献